Need a handy scapegoat? Call a plumber

When David Gauke, Exchequer Secretary to the Treasury, suggested that it was "morally wrong" to receive "a discount with your plumber by paying cash in hand," he was treading the well-trodden path of using plumbers as political wrenches.

Around 2004, they became the focal point of both anger and admiration in the UK for speculative reports on just how much they were earning.

And the practice isn't just confined to these shores. In 2005 "Le plombier polonais" became a buzz phrase in France, where it was used to describe the raft of eastern Europeans heading west.

In 2008 "Joe the Plumber" – real name Samuel Joseph Wurzelbacher, became a darling of the American right after he questioned the then presidential hopeful Barack Obama over his tax plans.

Nearly 40 years before President Richard Nixon created a different notion of "the plumber" when he tasked a covert group known as the "White House Plumbers", to plug leaks to the media. Some of its members later became involved in the Watergate break-ins.